Wall and floor construction of prestressed concrete



March 1, 1966 c. H. HuTcHlNGs WALL AND FLOOR CONSTRUCTION OF PRESTRESSED CONCRETE 5 Sheets-Sheet 1 Filed Jan. lO, 1962 ATTORNEYS March l, 1966 c. H. HuTcHxNGs 3,237,357

WALL AND FLooR CONSTRUCTION 0R PRRsTRRssED CONCRETE Filed Jan. lO, 1962 5 Sheets-Sheet 2 RTR' NSN

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March 1, 1966 Q H, HUTCHINGS 3,237,357

WALL AND FLOOR CONSTRUCTION OF PRESTRESSED CONCRETE Filed Jan. 1o, 1962 3 sheets-sheet s United States Patent 3,237,357 WALL AND FLOOR CONSTRUCTION F PRESTRESSED CONCRETE Carl H. Hutchings, 864 9th Ave. SE., Rochester, Miuu. Filed Jan. 10, 1962, Ser. No. 165,416 1 Claim. (Cl. 52-223) This invention relates to building construction, and more particularly to building construction wherein the walls and floors are of pre-stressed concrete.

The use of pre-stressed concrete structural members has increased greatly in recent years. -Where the prestressing is obtained by pre-tensioning particularly, units of great strength are obtained. In pre-tensioning cables are laid in beds and tensioned with powerful jacks against fixed jackheads, and held tensioned during pouring and setting of the concrete. When the cables are released they contract, putting the concrete in the area of the cables in compression. The cables are bonded to the concrete along their full lengths.

It has been proposed that this type of construction be used in the erection of houses and other buildings, but the very nature of the construction has necessitated formation of the building elements at a central plant having adequate pre-stressing bed facilities. This, in turn, called for the use of small elements suitable for easy transportation to the building side, or for the casting, of large units which were impractical to move. In either event, the construction was not feasible and little, or no use has been made of this form of construction in the building field.

The general object of the present invention is the pro- Vision of means to permit the casting of pre-stressed building elements in place in a building, or at the building side to eliminate transportation.

A more specific object of the invention is to provide a building construction which will allow a portion of the structure to be used as a pre-stressing bed for the casting of other parts of the structure.

Another object of the invention is the provision of a permanent part of the building structure as a perimetric jackhead for tensioning cables on the pre-stressing bed.

A further object is to provide a stressing bed on which several members may be cast at one time, with the stressing cables passing through adjacent units, to allow minimum stressing operations yet permit the several units to be separated by cutting the joining cables.

Still another object is to provide means whereby a single stressing cable, or group of stressing cables, may extend from one element to another of the finished structure, with the stressing operations for the several elements taking place sequentially.

Yet another object is the combining of the above mentioned principles into the construction of an atomic fallout, or bomb, shelter.

Other objects of the invention will become apparent from the following description of practical embodiments thereof, when taken in conjunction with the drawings which accompany, and form part of, this specification.

In the drawings:

FIGURE 1 is a top plan view of a building foundation structure made in accordance with the present invention, illustrating the structure used as a stressing bed;

FIGURE 2 is a vertical section through the structure shown in FIGURE 1, taken on the line 2-2 of FIG- URE l;

FIGURE 3 is a View similar to FIGURE 2 showing a modified foundation structure;

FIGURE 4 shows still another foundation, or basement, structure;

FIGURE 5 illustrates a poured footing and the forms 'ice set in place to pour a floor and jackhead similar to the arrangement shown in FIGURE 3;

FIGURE 6 is a vertical section showing the juncture of a vertical wall and a horizontal flooring, with stressing cables extending from the vertical wall into the flooring;

FIGURE 7 is a partial vertical section through a building having a basement suitable for use as a fallout shelter; and

FIGURE 8 is a section through a laminated pre-stressed panel having an insulating core.

Referring to the drawings in detail and first adverting to that form of the invention illustrated in FIGURES l and 2, there is shown a building foundation structure which forms a bed upon which pre-stressed concrete elements for constructing the remainder of the house can be made.

The foundation consists of a footing 1 of rectangular shape extending a substantial distance into the ground. The footing has a horizontally widened base 2, which provides broad upper shoulders 3 upon which earth fill 4 will be packed after the foundation is formed to securely anchor the footing in place and stabilize the footing against lateral shifting or tilting under the strain of tensioning stressing cables, as will be described. The footing and base will be of concrete suitably strengthened by steel reinforcing rods 5. The top of the footing is offset to provide a horizontal shoulder 6 and an upstanding jackhead 7 extending entirely around the top of the footing. Short lengths of pipe 8 are cast into the jackheads to form a plurality of horizontally extending openings 9 spaced at intervals along the entire jackhead. After the entire footing has been formed and set, the lill 4 is put in place and brought up to a horizontal plane a short distance below the shoulders 6 adjacent the jackheads. A floor 10 is poured upon the ll within the foundation and struck off flush with the shoulders 6.

With the above arrangement, an upstanding jackhead encompassing a rectangular stressing bed will be found. The bed will be as large as the contemplated building area, and the surrounding jackhead will have a plurality of spaced openings to allow for arrangement of stressing cables in desired patterns. The floor 10 may have openings 11 in predetermined pattern to provide for seating templates, or saddles, to hold reinforcing rods during pouring.

As shown in FIGURE 1, the bed may be used to form simultaneously a number of sections for use in completing the building. For example, gable end members 12 and 13, and wall panels 14, 15 an-d 16 may be cast al one time. To do this, a number of separator form members 17 will be set up upon the bed floor 10 to outline the sections to be made. These can be attached to the jackheads and to the door openings 11 as convenient. Suitable bracing 18 may be used between adjacent sections to hold the form members in proper spaced relation. Each of the form members will have spaced openings 19 to accommodate the stressing cables.

After the form members 17 have been set up, stressing cables 20 will be threaded through the openings 9 in the jackheads and the openings 19 in the form members to completely span the stressing bed. These can be arranged in any desired pattern, either longitudinally or transversely of the bed or both. It will be noted that in many instances the cables will traverse the space of more than one building section. One end of each cable projecting beyond the jackhead will receive a conventional anchor 21 to abut the outer face of the jackhead. A suitable jack 22 will be attached to the ,opposite ends of the cables in sequence, and each cable will be given the desired tension.

rment walls.

Additional anchors in the cable ends adjacent the jack will be seated against the jackhead to hold the cables in tension. Any desired reinforcing framework may be set up and the concrete poured and allowed to set. Window and door openings 23 and 24 and electrical conduits 25 and 'outlet boxes 26 may be positioned before the concrete is poured, so as to be cast in place. After the concrete has set, the cables may be cut at the jackheads and adjacent the form members to release the sections from the bed and to separate them from one another. The cables, of course, will be cut away at all window and door openings. 'Ihe resulting structures wil be pre-cast building sections which are pre-stressed and can be set up and attached to the existing foundation. It may be necessary that several castings be made on the bed in order to provide the desired number of building sections or panels.

In FIGURE 3, a slightly dierent arrangement is shown. Here, the footing 27, the floor 28 and jackhead 29 are closely adjacent, and little or no ll is required. This form includes the footing base 30 identical to the base previously described. The oor and jackhead are poured at one time on top of the previously cast base. To do this, forms 31 (see FIGURE 5) a-re set up in spaced relation t-o one another and the base by means of spacers 32. Pipe lengths 33 are supported between the forms to provide the necessary cable openings through the jackheads when cast. This can be done by having holes 34 through the form members and projecting pins 35 through these holes and the intermediate pipe sections. When cast, the foundation will provide a bed 36 similar to the one described. Cables 37 can be strung and tensioned, and concrete panels 38 ca'st on the bed.

As mentioned above, FIGURE shows the forms set up for pouring the floor and jackhead upon the base. It also shows that suitable reinforcing members 39 may be cast in the base and project upwardly for embedment within the jackhead to tie the base and jackhead together.

That form of the invention shown in FIGURE 4 differs only slightly from the forms previously described. In this case, the footing 40 has the same stabilizing 'base 41, vertical wall 42 rising centrally from the base, and an offset 43 at the top forming a shelf 44. This is substantially identical to the arrangement of FIGURES l and 2. In this form, however, no ll is put between the walls and the oor 45 re'sts upon the base. The walls 42 become basement walls and the offset 43 will serve as a ledge to support the panels which will be cast for the irst oor.

In order to provide a stressing bed, pipes 46 are cast in the walls 42 -just a short distance Vabove the base to provide the stressing cable openings 47. The walls, then, will serve as jackheads, and the panels will be cast upon the oor 45.

FIGURE 6 shows a construction where a footing, or vertical wall, 48 is reinforced by vertical cables 49. These could either be held taut during the pouring and setting of the wall 48, or, by means of temporary overhead jackheads, tensioned for pre-stressing. In either event, reinforcing rods 50 will 'be cast in the upwardly projecting tongue 51 of the wall and extend beyond the sides of the tongue. These will provide a plurality of guides about which the extending ends of the cables 49 can be turned to be tensioned in a horizontal plane to become the stressing members of horizontal floor panels 52. This will .allow for continuous stressing from one member to another, even though the adjacent members are not in alignment.

The above described structures and procedures can be 'utilized to produce an effective bomb, or fallout, shelter 53, as shown in FIGURE 7. This can consist of basement walls 54, set on bases 55, a basement roof 56, which serves at the same time as a flooring for the first floor of the building. The building walls 57 extend up from the base In most instance-s, earth till 58 will be used against the outside of the building walls to substantially Li. the height of the first floor so that the shelter portion of the structure will be underground.

The walls are preferably of laminated construction, consisting of various layers S9, 60 and 61 of concrete and one or more layers of a shock absorbing material 62. T he walls can be of pre-stressed construction, and may be formed as will be described in connection with the structure shown in FIGURE 8. Pre-stressing cables 63 are shown in the basement walls. The basement roof is shown as having a lower section of pre-stressed panels 64, covered by a layer of earth 65, or other shock-absorbing and iiltering material, with an upper section 66 composed of a plurality of pre-stressed panels laid upon the earth layer. It will be evident that this structure also can be used to provide a pre-stressing bed if desired.

In FIGURE 8, a laminated panel 67 is shown which will permit the construction of the concrete buildings with danger of condensation in the inside walls and without sacrifice of strength. The panel consists of two separated layers 68 and 69 of pre-stressed concrete, with a layer 70 of insulation between them. The insulation may be styrofoam, or other suitablel material. The concrete layers are stressed by cables 71 and 72 and the entire structure is tied together to form a unitary whole by reinforcing members 73.

In making the panel 67, reinforcing rods 73 of undulating form are placed in a stressing bed and held in upright position spaced slightly from the bed bottom. Stressing cables 71 are then strung in the bed between the jackheads with the cables in the corners of the U-forms of the undulating reinforcing rods. The cables are tensioned and a layer of concrete of suitable depth for the panel layer 68 is poured. The insulation layer 70 is placed upon the layer 68, and cables 72 are then strung in the stressing bed. These latter cables are placed so that they rest, when tensioned, in the corners of the inverted U- forms of the reinforcing members. The top layer 69 of concrete is then poured. When the entire structure has set and the cables are released, the panel will consist of two pre-stressed layers with the layers held in position by the reinforcing members imbedded in the concrete and interlocked with the stressing cables.

While various embodiments of the invention have been disclosed, it will be apparent that changes in structure from the precise details shown and described can be made within the scope of the appended claim.

What is claimed is:

In a building, a vertical member and a horizontal member having one end seated on the vertical member, tensioned stressing cables extending unbroken through the said members having reaches extending vertically through the vertical member and horizontally through the horizontal member, and means carried by one of said members about which the cables turn at the juncture of the vertical and horizontal reaches of the cables, whereby the vertical and horizontal members are prestressed and the members are held in assembled relation, the vertical member being recessed adjacent its top to `form an upstanding tongue and a horizontal shoulder and the horizontal member being seated on the shoulder, and the means about Which the cables turn being reinforcing rods embedded in the tongue and extending into the end of the horizontal member seated on the shoulder.

References Cited by the Examiner UNITED STATES PATENTS` 1,557,523 10/1925 fHahn 52-583 X 2,182,470 l2/1939 Erdman 52-410 2,301,602 11/1942 Wohl 52-410 2,435,998 2/1948 Cueni 52-223 2,459,415 1/ 1949 Cibulk-a 52-302 2,490,537 12/1949 Myer 52-234 2,786,349 3/1957 Cotf 52-223 (Gther references on foilowing page) l.. u 6 UNITED STATES PATENTS 144,126 2/ 1954 Sweden. 2,871,544 2/1959 Youtz 52 745 240,414 4/1946 Switzerland- 2,878,665 3/1959 Crabbe 52-169 OTHER REFERENCES g r- 5 Construction Methods, March 1946, pp. 10s-109, 3015912 1/1962 Fisted 5, 742 Engineering News Record, Sept. 14, 1950, pp. 48, 49. 3023475 3/1962 Yerby 2 118 Engineering NGWS RECOICL7 Jan. 28, 1954, pp. 48, 49. 3,053,015 9/1962 Graham 52 534 Scientific American, July 1958, v01. 199, No. 1, pages FOREIGN PATENTS 10 P25-28' 965,651 2/1950 France. FRANK L. ABBOTT, Primary Examiner. 3381864 11/1930 Great Bfltam JACOB L. NACKENOFF, HENRY C. SUTHERLAND,

639,399 6/1950 Great Britain.

806,119 12/1958 Great Britain. Exammefs. 

